Suction-roll.



a. HELLSTR QM. SUCTION ROLL. APPLICATION FILED APR-23. 19H- lfi kmn Patented. July 24,1917.

2 SHEETS-SHEET I.

e. HELLSTR'O'M.

SUCTION ROLL. APPLICATION FILED APR-23,191].

htented July 24:, 191?.

2 SHEET$+SHEET 2.

, fication.

GSWAY, LONDON,

suc'rromaom.

reaches,

Specification of Letters Patent.

Patented July as, ran a Application filed April 23,1917. Serial No. 168,884.

To all whom it may concern:

Be it known that I, GUSTAF a subject of the Kingof Sweden, residing at Kingsway, in the county of L 'ndon, England, have invented Improvements in Suction Rolls, of vwhich the following isaspecisuction roll con unction with such a suction roll for of other material (hereinafter included in This invention relates to that of forpaper making machines, drying mac es, pulp vats and Similar apparatus, wherein a suction box is used in the extraction of water from the paper, or pulp, or felt sheet or web, or sheet or web the term wet sheet).

The present invention has for its ob ect to prevent or minimize clogging of the perforasurface thereof in J statlonary separating vantage be arranged to 65 tions in the periphery of the suction cylinder by fibersor the like that maybe drawn into them by suction from the wet sheet and thus to enable the suction effect to act in a more continuous uniform and advantageous manner than heretofore for removing water from the wet'sheet For this purpose, the suction effect is caused to take place through opposite portions of the perforated cylindrical wall of the suction roll (hereinafter referred to for brevity as the roll wall) and the intermediate interior of the roll and thence through a suction boxarranged external to and bearing against the outer surface of the roll wall at a portion thereof that is, for'the time being, opposite to the portion thereof over w roll rotates, liquid will be drawn'from the wet sheet in an inward direction through a portion of the roll wall into the interior of the roll and in an outward direction from the interior of the roll through the roll wall opposite the suction box. Those portions of the roll wall that are not covered either by the wet sheet 01' by shut ofi from the interior of the roll and the suction box bymeans, such as stationary dividing off I or separation walls, arranged within the roll and fitting a anair tight manner, so that the suction efl'ect can-only take place through the ortions of the roll wall covered by the wet's eet and the suction box. The

form open boxes or chambers preferably in communication with atmosphere. I

Hnus'rnom,

- of the suction roll hich the wet sheet extends, so that, as the the suction box are" gainst the inner walls may with ada In the accompanying drawing, Figure 1 shows in vertical transverse section and Fig. 2 in central longitudinal section, a suction roll arrangement according to the invention.

In this example, 1 is the suction roll having a perforated periphery and 2 is one of the two end bearings for the roll. 3 is the wet sheet which passes over the roll and om which water is to be extracted. Rollers 4 and 5 serve to guide the Wet sheet at the points where it meets and leaves the suction roll. The perforations 1 in the roll wall may be of inwardly ta ering shape, and are covered by a perforated mantle 6 of suit able metal, for example copper.

7 is a stationary suction box arranged at the lower part of the suctionroll. This box opens toward the roll and is in communication' through a pipe 8 witha suction, air pump 8 and is provided with a pipe 9 to conduct away the extracted water. A fluid tight joint is produced between the suction box and the 'roll by suitable packing means, such, for example, as packing bars 10 arranged to slide in grooves in the side walls of the box and pressed against the suction roll by springs 11.

A stationary pipe 13 that passes in an air tight manner through the end walls of the suction roll and through the center of the roll, carries by means of hollow arms 13, two dividing ofi' boxes or chambers 14 and 15 which are open toward the inner surface between the parts of the roll coveredby thewetsheet and suction box and bear in a'fluid tight manner against the inner surface of the roll in the same way as the suction box 7 bears against the outer surface of the roll. The boxes 14 and 15 are in communication with the external atmosphere through the hollow arms 13 and the centralp'pe 13. At the same time, air can enter the said boxes throu roll wall 0 posite the sai such parts atmospheric. ressure prevails at both sides of the roll 'wa 1. As the boxes 1% and 15 cover those portions of the surface of the suction roll which boxes, so that at it is evident that air and water can only be drawn into the roll by suction through that part of the roll covered by the wet sheet.

ranged at each end of and within the suction roll' is a movable annular cover 16 that is carried by a disk 16 and is adjustable longitudinally, as by screws 17 operated,

h that part of the l are neither covered a by the wet sheet 3 nor by the suction box 7,

from the outside and extending in an air tight manner through the adjacent end wall of the roll. By moving the covers longitudinally so as to cover a smaller or greater part of the perforated wall of the roll, the roll, can be readily adapted totreat wet sheets of different widths.

The action of the improved suction roll arrangement is as follows When air is sucked through the pipe 8 and a partial vacuum thereby created in the suction box '7 and in the interior of the suction roll 1, water will be sucked out of the wet sheet 3 covering the upper part of the roll, such water passing through the perforations in the mantle 6 and in the roll wall into, the interior of the roll and thence through the perforations in the opposite portions of the roll wall into the suction box 7 from which it is discharged by the pipe 9. The discharge is preferably suitably regulated by a valve '9 so as to maintain a certain water level in the suction box. At the same time the two boxes 14 and 15 prevent any air from being sucked into the roll through those parts thereof which are neither covered by the wet sheet 3 nor by the suction box 7. It is obvious that when water is sucked from the wet sheet, some fibers may pass through the perforated mantle 6 and enter the small holes in the wall of the suction roll. As the roll turns, and as the water is extracted from the inside toward the outside by thesuction box 7, the water will wash out any fibers which may have entered the holes and in this way render the roll self-cleaning, which is of great importance.

The suction roll can be used either in combination with a pressure roll 19 or not, as may be desired.

What I claim is a 1. The combination with a suction roll' and means for leading a wet sheet from which liquid is partly around a ortion of the perforated cylindrical wall 0 said roll, of a suction box arranged external to said roll and in fluid tight connection with the outer surface of another portion of the perforated wall of said roll and means located within said roll adapted to close communication between the suction box and the external atmosphere through those portions of the perforated roll wall not covered by the wet sheet under treatment and the suction box.

2. The combination with a suction-roll,

means for leading a wet sheet on to a portion of the perforated wall of said roll and means for leading-the sheet away from said roll, of a stationary external suction box opening toward another portion of the erforated roll wall, means ada ted to ma e a fluid'ti ht joint between sald' suction box and r0 means to be extracted, over and for drawingair from said suction boxand the interior of said roll, means for leading away liquid from said suction box and means within said roll closing communication between said suction box and the atmosphere through those portions of the perforated roll wall not covered by the wet sheet and suction box.

3. The combination with a suction roll, means for leading a wet sheet on to a portion of the perforated wall of said roll and means for leading the sheet away from said roll, of a stationary external suction box opening toward another portion of the perforated roll wall, means adapted to make a fluid tight joint between said suction box and roll, means for drawing air from said suction box and the interior of said roll means for leading away liquid from said suction box and stationary separation walls, arranged within said roll and covering those portions of the perforated roll wall not covered by the wet sheet and suction box.

4. The combination with a suction roll,

tion of the perforated wall of said roll and means for leading the sheet away from said roll, of a stationary external suction box opening toward another portion of the perforated roll wall, means adapted to make a fluid tight joint between said suction box and roll, means for drawing air from said suction box and the interior of said roll, means for leading away liquid from said suction box and stationary boxes constitutin separation walls, within said roll,

said oxes opening toward and fitting in a 'means for leading a wet sheet on to a porof the perforated wall of said roll and means for leading the sheet away from said roll, of a stationary external suction box 0 ening toward another portion of the er orated roll wall, means adapted to ma e a fluid tight joint between said suction box and ro 1, means for drawing air from said suction box, and the interior of said roll, means for leading away liquid from said suction box, stationary boxes constituting separation walls, within said roll, said boxes opening toward and fitting in a fluid tight manner against the inner surface of the erforated roll wall and covering at the inside the parts thereof not covered at the outside by the wet sheet being treated and the suction box and means for placing said boxes in communication with the external atmosphere through the end walls of said roll. I

6. he combination with a' suction roll, means for leading a wet sheet on to a portion of the perforated wall of said roll and roll wall opposite which t aaeaaee means tor leading the sheetaway from said roll, of a stationary external suction box opening toward another portion of thep'erforated roll wall, means adapted to makea fluid tight joint between said suction box and roll a stationary pipe extending hollow arms fixed to said pipe, boxes carried by said arms and opening toward the inner surface of said roll and means for efiecting air tight joints between, said boxes and'the innersurface of said roll, said. boxes being arranged opposite those parts of the roll wall that are between the parts thereof covered by the wet sheet under treatment and the suction box and in communication with the external atmosphere through said arms and pipe and through the perforated ey are arranged.

7. The combination with a suction roll and means for leading a wet sheet from" which liquid is to be extracted, over and partly around a portion of the perforated cylindrical wall of said roll, of a suction box arranged externalto said rolland in fluid tight connection with the outer surface of another portion of the perforated wall of said roll, means located Within said roll means for drawing air from 'said suction box and the interior of said roll,, means for leading away liquid from said suction box,

centrally through said roll and its end walls,-

adapted to close coun-ication between the I suction box and the external atmosphere through those portions of the perforated roll wall not covered by the Wet sheet under treatment and the suetionbox, and endwise adjustable means adapted to mask the perforations in portions of roll wall.

8. The combination with a suction roll and means for leading a Wet sheet from. which liquid is to beextracted, over and partly. around a portion of theperforated cylindrical wall of said roll, of a suction box arranged externa to said roll and fluid tight connection ith the outer surface of another portion of the. perforated Wall of said roll, means located Within said roll adapted to close communication between the suction 'box and the external atmosphere threugh those portions of the erforated roll wall not covered by the wet s eet under treatment and the suction box, and longitudinally adjustable annular covers ar- Witnesses: v I

R. A; UGr, Ivan lli mirnonen,

' roll and mask perforations in the roll enerarnjntts rlabin 

